This invention relates generally to archery bows, and more specifically to archery bow limbs and methods of making same.
Current high performance archery bows generally employ bow limbs composed of composite materials, typically fiber glass and/or other reinforcement in a thermoset resin matrix. Examples of these bow limbs and materials are disclosed in U.S. Pat. Nos. 2,980,158; 4,318,762; 4,323,415; 4,649,889; 4,735,667; and 5,501,208. While these bow limbs are suitable for many of today's compound bows, the manufacturing process has a number of areas that require very close controls. Further, even with the controls, it can be difficult to produce a void free product, and considerable hand work and secondary operations are required to trim and prepare the bow limb for use.
Thermosets used in bow limbs, such as epoxy or polyester, are inherently brittle and are formed by a chemical reaction. Thus, thermosets cannot be remelted or reformed once set.
Thermoplastic materials by contrast are generally tough and can be remelted. The raw materials are generally cheaper than thermosets and have a much longer shelf life. However, the use of thermoplastics in archery bow limbs is limited.
U.S. Pat. No. 5,534,213 teaches the use of a glass filled thermoplastic material to injection mold a bow limb. These bow limbs are limited to use in bows of very minimal draw weights, for example having a maximum peak draw weight of less than 25 pounds.
There remains a need for a thermoplastic bow limb having the high strength required for use in current high performance archery bows.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.